Refrigerating apparatus



1943- A. A. KU CHER 2,336,549

REFRIGERATING APPARATUS Filed Nov. 28, 1941 3 Sheets-Sheet 1 Q I M I NVENTORQ MW MM? Dec. 14, 1943. A, KU H R 2,336,549

REFRIGERAT ING APPARATUS Z 4 %M INVENTOR. BY MM Dec. 14, 1943. KUCHER 2,336,549-

REFRIGERATING APPARATUS Filed Nov. 28, 1941 3 Sheets-Sheet 3 BLOWER MOTO &

O or- 4, 102:

{:1 IMWXMINVIENTOR.

BYM M Mu Patented Dec, 14, 1943 2.33859 mwzmsnarma arraaa'rns .ml sxueher, omoommae, assignor to, W"Motors'Corporation;-' Dayton, Ohio, a

' fibrii'otatidn of Delaware "SClaims.

This invention to refrigerating 8l paratus and more particularly to apparatus suite able for use in conditioning the air for a private. home or the like.

One object or this invention is to provide an improved type of air conditioning unit' suitable. in the attic of a private homeor for mounting the-like. I 2

Another object of this invention is to provide air conditioningappcratus designed to conn Z1uon 100% fresh air irrespective of outside air temperatures;

Still another object of this invention to provide a system in which the capacity of the system may be adjusted in a manner so as not to sacrifice iltis t A fur er object of this invention is to eliminate'the necessity for making a large number of diirrent sized air conditioning units.

More particularly, it is an object of this invention to connect two or more similar refrigeratrequired and the necessity for manufacturing a ing units in tandem when one unit alone would have'insufliclent-capacity, and to provide imranged in tandem. I Further objects and advantages of the present invention'will be apparent from the followingdescription, reference being"'had'to the accompanyingdrawings, wherein a preferred form of the present invention is clearlyshown;

-In'the drawingszs Fig; 1 is a vertical sectional view somewhat diagrammatic showing a tandem air conditioning unit constructed in accordance with my invention and installed'in a private home;

' Fig. 2 is a perspective view intended us show the construction of the plenum chamber and proved means ior'controlling'the units when arthe method'of securing-the'plenum 'chamberto the main air conditionin g unit;

Fig. 3 is a vertical sectionalvieiv taken 'online 3-3 of Fig. .4 showingthe-g'eneralarrangement ofasingleunit.

--Fig-.'4'-is' a vertical sectionalview taken on line 7 4-4 of Fig. 3; and

Fig. 5 is a sectional. view largely I cults and the electrical'cireuits toga principal controls. Even though private homes require summer? conditioning just as badly as ofilces-and other commercial establishments, very few homes have systems. One of the principal reasons for this is that the cost'of an air conditioning system. capable of conditioning the air .for a private home has been prohibitive. One reason for thishigh cost has been that the most satisfactory prior art systems have required complicated and expensive-air distributing ducts. Furthermore, the

cost of operating the prior art systems has been excessive in comparison with the cost of operating showing the refrigeration circuits, the water-cl .isrwim e been equipped with summer air conditioning Application November-'28, 1941, Serial No. 42o,sss

a designed in accordance with my invention. Another. reason for the high cost of the prior art air conditioning units is that different sized units have been requiredfor diflerent sized homes. It is obvious that the cost of manuiacturlng a -given number of units is much greater if these units are not all the same size. By virtue of my improved construction, no air ducts are large number of diflerent sized home' air conditionin'g units has beeneliminated.

, In Figs. 2, 3 and 4, I have shown a single air conditioning unit which may be placed in'the.

attic of a homefor conditioning the air for the home. The construction andarrangementof the unit issuch that it may be used. alone or it may be arranged in tandem with one or more similar units for conditioning the air for the; home.- Each unit comprises a main cabinet It which houses. a refrigerant evaporator II, a sealed motor-compressor-c'ondenser unitll connectedin refrig-- erant flow relationship with the evaporator 12, and a blower unit It driven by blower motor it through thebelt 20; For a moredetailed .description of the motor-compressor-condenser.

un it ,reference is hereby made'to my co-pendingv application. Serial Number 326.853, flied March 30, 1940, now'Patent. No.- 2,2 86,491, issued June 16,1942.-. Refrigerant vaporizedfln the evaporator I2 returns-to the unit-ll through the line liandliquid refrigerant issupplied. to the evaporator through; the line 'l 'l. Reference numeral [9 designates a refrigerant control de- *vice which maybe either a fixed 'restricto or an expansion valve.

, a plenum chamber .22, lined with insulating I material 28, is arranged adjacent the bloweroutlet 2'4. This plenum chamber .22 is removably secured to the main cabinet it merely by-hooking the flange over the bracket 38 which is carried by the wall of the main cabinet Ill. Sta- 1 tionary lugs 40 carried by the cabinet l0 cooperate with the notched flanges 42 on' the plenum chamber 22 so as to removably hold the plenumchamber 2'2 in place once the chamber is lowered into place.

plenum chamber, as shown-:inqRig. 2, through wardly into the conditioned space.

As shown in Fig. 1 wherein two of these units have been shown connected in tandem, the conditioned air is discharged into the upper :hall from whence theair is distributed to the various rooms through the hallways. An air distributing plaque 32 is provided for directing the air substantially horizontally along the ceiling of the second floor hall. Since every house has a different arrangement of'rooms, it'is obvious that y A-baille -28 is-provided the plenum chamber fordirecting the flow ofalir'within the chamber. an air outlet fop'eriln'g '30 isprovidedin-the-bottbm Wall of the which the conditoned air'is discharged down- I the supply line 52.

, known practice.

the arrangement shown in Fig. 1 has been shown for purposes of illustration only and that the apparatus is equally applicable to one-story homes. It is also obvious that the conditioned air may be discharged me some room other than the hallway if desired. In the arrangement shown in Fig. 1, all of the air to be conditioned enters the attic space :through the attic win-.

dow 3B, and enters the cabinet I! through the inlet 25. A filter 21 is provided adjacent the in et 25. v e

When it is desired to provide an air conditioning system having a capacity greater than the capacity of a single unit, two units are connected in tandem, as shown in Figs. 1 and 5. When two units are connected in tandem, the conditioned air leaving the first plenum chamber discharges into the inlet 25 of the second cabinet I through an adapter 44. When two units are connected in tandem, a new outlet opening 40 is provided in the first plenum chamber, as shown in Fig. 5,

\ through which the air discharges into the second unit.

Inasmuch as there are many localities in which the condenser cooling water is sufiiciently cool to be usable in precooling the relatively hot incoming fresh air, each unit is designed so that a water coil 60 may be mounted ahead of the evaporator, as best shown in Figs. 3 and 5. When two units are connected in tandem, the

- water coil is omitted from the second unit since the air leaving the first evaporator wouldbe cooler than any water normally available.

Referring now to Fig. 5 in which the water connections are shown, reference numeral 52 designates the main water supply line through which cooling water from any convenient source, such as the city water mains, is supplied. Pipe line connects the air cooling coil 50 with The water leaving the coil 50 is used for cooling the" condenser of the first tandemunlt and is supplied to the interior of the motor-compressor-condenser unit I of the first unit through the line 50. The water leaves this motor-compressor-condenser unit through the line 50 which connects to the water drain 00.

The flow of water through the coil 50 and its associated motor-compressor-condenser unit It is controlled by means of a valve 62 which is regulated in response to the pressure within the condensing chamber, in accordance with well A small tube 01 connects the pressure operated valve 02, with the interior of the condensing chamber.

During light loads, only one of the tandem units is required to operate. When the capacity of the one unit is insufficient for properly cooling the air, a second unit is automatically placed into operation, as will be explained more fully hereinafter. When the second unit is in operation, water from the main supply line 52 flows directly to the condensing portion of the second motor-compressor-condenser unit I 4 through the line 65. The water leaves the second unit I4 through the line 60 which also connects to the drain line 00. The fiow of condenser cooling water through the second motor-compressorcondenser unit It is controlled by a valve 98 which is similar in construction and function to the valve 02. A small tube I0 connects the valve 68 with the condensing chamber of the unit ll. Each water control valve functions in its usual well known manner tooldse oi! the supply of manually or automatically so as to render the entire air conditioning system ineffective. Electrical energy is supplied to both" of the blower motors I8 through the lines 04., A thermostat 00 located adjacent the inlet to the first unit, and i which therefore responds to the temperature of the outside air, controls the operation of the switch 88 which renders both blowers ineffective when the outside temperature falls so, low that the outside air is unsuitable for forced ventilation purposes. A manual switch 90 is provided in the circuit leading to the blower motor of the first unit and a corresponding manual switch 92 is located in the circuit leading to the blower motor I 0 of the second unit so that either one or both of the blower motors may be stopped independently of the automatic control described hereinabove.

A switch 94 is provided in the circuit leading to the motor-compressor-condenser units ll.

This switch may be controlled either manually or automatically. In order to simplify this disclosure, no automatic control has been shown for operating the switches 02 and 94, but it is within the purview of this invention to provide either a dry bulb thermostat, a wet bulb thermostat, or a combination of the two for controlling these switches. The controls may respond to the condition of the incoming air or to the condition of the air within the disclosure, or to both.

In order to prevent excessive loading of the electrical circuits, I have provided means for preventing both of the motor-compressor-condenser units from starting up at the same time. This means comprises a switch 96 which does not close until a predetermined time interval after the motor-compressor-condenser I4 of the first unit has been energized. The switch 90 is closed by means of the solenoid 98. A dash pot I00 has .been provided for retarding the closing movement ofthe switch 96. Thus, upon energization of the solenoid 98, the switch-96 is biased to the closed position but does not move immediately to the closed position due to the retarding action of the dash pot I00. Since both units are not required to operate at all times, I have provided automatic means for rendering the second unit condenser cooling water when no water is required; The tubes 94 and 10 are preferably atineffective whenever the air conditioning load is such that the first unit has ample capacity. This means comprises a thermostat I02 located adjacent the inlet of the second unit. The thermostat I02 is adjusted so as to open the switch I04 whenever the temperature of the air leaving the first unit is sufliciently cool for discharging into the conditioned space. By virtue of this arrangement, both units normally operate when the outside air temperatures are so high thata single unit would have insufficient capacity to properly cool the air, and only the first unit operates when it alone has sufficient capacity to properly condition the air. Manual switches I05 make it possible to individually control each compressor unit.

In a system inwhich the major portion of the air is recirculated and the air is cooled to a temperature of or at the outlets, and the operating back pressures in the refrigerating system, when using difluoro-dichloro methane as a refrigerant, are maintained between 30 and 38 pounds, approximately 30% of the work produced is recovered by recirculating the air. The thermal eificiency of such systems usually approximates or 12 B. t. u. per watt input.

In a system constructed in accordance with my invention in which a greater amount of air is cooled and in which all of the air is fresh outside air, and in which the air is cooled to a temperature of- 65 or 70 at the outlets and the operating backpressures in the refrigerating system, when using difiuoro-dichloro methane as a refrigerant, are maintained between 42 and 50 pounds, the thermal eificiency approximates 18 to 20 B. t. u. per watt input, whereby the relative increase in thermal eificiency more than compensates for the recovery in a recirculating system. I

This thermal efi'iciency runs much higher in those installations in which the available cooling water may be used in precooling the relatively hot outside air. In fact, the thermal efflciency of such a system commonly runs as high as 28 B. t. u. per watt. By virtue of this fact, it is obvious that a small inexpensive system is provided which makes it possible to condition all fresh air at a very low cost. I

The expression self contained unit is used to designate a unit in which a common support stream, means responsive to the temperature of the air leaving said first evaporator for controlling the flow of refrigerant to said second evaporator, means for flowing water in thermal exchange with said air stream, and means utilizing said water for cooling a portion of one of said refrigerant systems.

4. Air conditioning apparatus for conditioning the air in a private home or the like comprising in combination, means for flowing a stream of air into the space to be conditioned, a first refrigerant system having an evaporator located in said air stream, a second refrigerant system having an evaporator located in said air stream,

is provided for the compressor, condenser and evaporator and holds these elements in flxed relation at all times.

While the form of embodiment of the invention asherein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow:

What is claimed is as follows:

1. Air conditioning apparatus comprising in combination, a first volatile refrigerant air con ditioning unit, a second volatile refrigerant air conditioning unit, each of said units comprising an evaporator, a compressor and a condenser, means for circulating a stream of fresh air over said evaporators in series, a water coil arranged in said air stream, means for flowing water through said water coil and thereafter in thermal exchange with one of said condensers, and means for rendering one of said evaporators ineffective during light air conditioning loads, said last named means comprising a thermostatic means responsive to the temperature of the air leaving the first of said evaporators for controlling the now of refrigerant through said second evaporator.

2. Air conditioning apparatus for conditioning the air in a private home or the like, comprising in combination, means for flowing a stream of outside air into the space to be conditioned, a first refrigerant system having an evaporator located in said air stream, a second refrigerant system having an evaporator located in said air stream, means responsive to the temperature of the air leaving said first evaporator for controlling the fiow of refrigerant to said second evaporator.

3. Air conditioning apparatus for-conditioning the air in a private home or the like, comprising in combination, means for flowing a stream of outside air into the space to be conditioned, a first refrigerant system having an evaporator located in said air stream, a second refrigerant system having an evaporator located in said air thermostatic means responsive to the temperature of the air flowing from said first evaporator to said second evaporator for controlling the cooling of air by said second evaporator.

5. Air conditioning apparatus for conditioning the air in a private home or the like, comprising in combination; a first self-contained air conditioning unit including an evaporator, a compressor, and a condenser; a second self-contained air conditioning unit comprising an evaporator, a compressor, and a condenser; means for directing air to be conditioned in thermal excLange with the evaporator of said first unit and there after in thermal exchange with the evaporator of said second unit; and means responsive to the temperature of the air leaving the evaporator of said first unit for controlling the cooling of air by said second evaporator.

6. Air conditioning apparatus for an enclosure comprising in combination, means for flowing a stream of outside air into the space to be conditioned, a first portable self-contained refrigerant system having an,evaporator located in said air stream, a second portable self-contained refrigerant system having an evaporator located in said air stream, means responsive to the temperature of the air leaving 'said first evaporator for controlling the flow of refrigerant to said second evaporator, means for flowing water in thermal exchange with said air stream,- and means utilizing said water for cooling a portion' of one of said refrigerant systems.

7. Air conditioning apparatus for conditioning the air in a private home or the like comprising in combination, duct means for directing a stream of air into the spaceto be conditioned, a first refrigerant system having a blower and an evaporator located in said air stream, a second refrigerant system having a blower and an evaporator located in said air stream, thermostatic means responsive to the temperature of the air flowing from said first evaporator to said second evaporator for discontinuing the cooling of air by said second evaporators while maintaining operation of said second blower.

8. Air conditioning apparatus for conditioning the air for a private home or the like comprising in combination, duct means for directing a stream of air into the space to be conditioned, a first refrigerant evaporator and blower located in said air stream, a second refrigerant evaporator and blower located in said air stream, means for supplying refrigerant to said evaporators, thermosponsive to the incoming air temperature controlling the operation of said blowers.

ANDREW A. KUCHER. 

